The sentence is in indirect speech and the reported speech consists of a fact which is universally true. As we know that a univerally true fact is always kept in simple present, so, the use of auxiliary verb "was" is incorrect in the sentence and must be replaced by "is". So, option A is correct.

In questions beginning with an auxiliary verb (need, must, should, could), the first verb doesn't take an infinitive. However, to after go is the second infinitive position, hence will follow.

Hence, option C is the correct answer.

Before "been" participle "has, have or had" is used. Since the subject is singular. Therefore singular verb should be used. So the sentence is grammatically correct.

When two nouns of different number or person are joined by "as well as" the verb should agree with the former subject. In the given sentence, the first subject is "his parents", so the verb should agree with this and should be in plural form. A plural verb "are" is given in option C only, hence, it is the correct answer.

When two singular nouns are joined by "neither.....nor", the verb must agree to the nearer subject. In the given sentence, the closest subject to the verb is "he" which is a singular subject. Therefore, the correct verb should be singular which is "is" instead of "are".

Therefore, option B is the correct answer.

The phrase "get the better of" is correct which means to fool someone. Thus, option A is the correct answer.

The use of preposition "below" is incorrect in the sentence. "Below" is related to the idea of "lower or less than". See its use in the below examples:

The sun disappeared below the horizon.

The movie is not suitable for children below the age of 18.

The correct preposition to be used in the given sentence is "under" as it also means "to be guided or controlled by". See below example:

He was not happy working under the new boss.

The army won all the battles under the command of new general.

The word "altar" is a noun here and it means a type of table used in ceremonies in a Christian church or in other religious buildings. Altar is the most suitable word contextually. The correct preposition to be used here is "on".

The correct sentence is given in option A. 

In structures as given in the sentence, we use article "the" with both the comparative adjectives. See some example:

The more you practise, the better you become.

The faster you walk, the sooner you will reach.

The bracketed part is incorrect as the sentence is in the present tense and the bracketed part is in the past tense. The qualities have been mentioned in a sequence, hence the repetitive introduction of the subject is not required.  

Hence, option A is the correct option.