The correct answer is Option 2 i.e. No Improvement.

• A finite subject needs a finite verb.
• Subjects and verbs must AGREE with one another in number (singular or plural). Thus, if a subject is singular, its verb must also be singular; if a subject is plural, its verb must also be plural.
• The subject of the given statement is "People" which is plural hence, we need a plural verb here.
• The underlined part of the given statement follows the given rule itself hence, "No Improvement" will be the correct choice.

Correct Sentence:-

Some people seem to take great delight in hearing about the misfortunes of others.

The correct answer is Option 3 i.e. satisfactorily explained by.

• "Modal verb + be + past participle" is the correct verb phrase.
• In the passive structure, we use "By + agent".
• The chosen option follows the given rules hence, it will IMPROVE the statement correctly.

Correct Sentence:-

Balpakram has many mysterious and unnatural phenomena that cannot be satisfactorily explained by modern science and logic.

The correct answer is Option 4 i.e. guilty.

Let's have a look at the meaning of the given options:-

1. guilty- having broken a law; being responsible for doing something wrong.
2. innocent- not guilty of a crime or offence.
3. insane- crazy or mentally ill.
4. liable- responsible by law; legally answerable.

"Guilty" which means "having broken a law; being responsible for doing something wrong" fits in the context appropriately.

Hence, it will be the correct choice.

Correct Sentence:-

Justice has prevailed; the guilty man has been punished.

The correct answer is Option 3 i.e. once.

• We use "once" to mean 'at a time in the past but not now'.
• In this meaning, we often use it in mid position (between the subject and the main verb, or after the modal verb or first auxiliary verb, or after be as a main verb).

For example:-

• My father once worked on an oil rig. (He no longer works there.)
• The chosen option suits the given blank hence, it will be the correct choice.

Correct Sentence:-

B.R. Ambedkar once said, "fraternity can be a fact only when there is a nation."

The correct answer is Option 3 i.e. who.

• A relative pronoun is used to connect a clause or phrase to a noun or pronoun. The clause modifies or describes the noun. The most common relative pronouns are who, whom, whose, which, and that. 
• A relative pronoun is used according to the nature of the antecedent.
• "Who" is used as the relative pronoun if the antecedent is a person.

"Teenager" shows a person hence, the chosen option will be the correct choice.

Correct Sentence:-

As a teenager who avidly loves science, I am shocked by the number of people who support astrology and affiliated courses.

The correct answer is Option 4 i.e. Not anticipated.

• In the given question we need to select the meaning of the given idiom.
• An IDIOM refers to "a group of words established by usage as having a meaning not deducible from those of the individual words".

Let's have a look at the meaning of the given idiom:-

• Out of the blue- without warning; unexpectedly.
• For example:- One night, out of the blue, she knocked on my door.

The meaning of the given idiom is the same as the chosen option hence, it will be correct.

The correct answer is Option 1 i.e. Disinherit someone.

• In the given question we need to select the meaning of the given idiom.
• An IDIOM refers to "a group of words established by usage as having a meaning not deducible from those of the individual words".

Let's have a look at the meaning of the given idiom:-

• Cut off without a shilling- disinherit; to refuse to let somebody receive any of your property after you have died.
• For example:- My parents have threatened to cut me off without a shilling once I turn 30, so I really need to find a job.

The meaning of the given idiom is the same as the chosen option hence, it will be correct.

The correct answer is Option 2 i.e. Concur.

Let's have a look at the meaning of the given options:-

1. Commiseration- sympathy and sorrow for the misfortunes of others; compassion.
2. Concur- to agree.
3. Commodious- roomy and comfortable.
4. Convenient- suitable or practical for a particular purpose; not causing difficulty.

As the chosen option is correctly spelt it will be the correct answer.

The correct answer is Option 3 i.e. Buvine.

Let's have a look at the meaning of the given options-

1. Bravado- a bold manner or a show of boldness intended to impress or intimidate.
2. Besmirch- damage (someone's reputation).
3. Bovine- relating to or affecting cattle.
4. Baffle- to be impossible to understand; to confuse somebody very much.

As the chosen option is incorrectly spelt it will be the correct answer.

The correct answer is Option 1 i.e. Entire.

Let's have a look at the meaning of the given options:-

1. Through- in or to every part : completely; from beginning to end of an experience or activity, typically one that is tedious or stressful.
2. Entire- whole or complete.
3. Resplendent- brightly coloured in an attractive and impressive way.
4. Grand- magnificent and imposing in appearance, size, or style.
5. Grim- (used about a person) very serious; not smiling.

As the chosen option expresses the best meaning of the given word it will be correct.