Sensory neurons receive sensory inputs from the internal and external environment and transmit them to CNS (brain and spinal cord) for processing.  Motor neurons transmit the nerve impulses from CNS to effectors (muscles and glands).  According to the signal, carried by motor nerves to effector organs, the muscles and glands perform their actions (contraction and secretion respectively) and thereby coordinating the metabolic activities. 

The two main types of cells of the nervous system are neurons and neuroglia. The myelinated axon fibres are covered with white myelin sheath formed from the membranes of tightly spiraled neuroglia cells. 

Hence, the correct option is (C).

The cell wall is absent in Mycoplasma.

Mycoplasma is a genus of bacteria lacking a cell wall around its cell membrane. This property makes them naturally resistant to all the antibiotics which target cell wall synthesis. Mycoplasma can be parasitic or saprotrophic. Bacteria are unicellular microscopic organisms that can be found in a diverse environmental state. Sometimes bacteria can be helpful like curding milk and digestion of food in the human gut. Plants are multicellular eukaryotes of the kingdom Plantae. Funaria is a genus of moss. Funeria hygrometrica is the most common species which is called cord moss because of the twisted seta. The name funeral is derived from the Latin word 'funis' means a rope.

Hence, the correct option is (A).

Fertilization results in the formation of a zygote that takes place in the oviduct. This zygote then undergoes a series of changes before it actually gets implanted in the uterus. Zygote first undergoes cleavage and results in the formation of 16 cells known as a morula. This is a solid ball and is represented by figure a. The morula then enters the uterus and undergoes changes. The 16 celled morula further forms 32 cells and these then start arranging in two layers: outer trophoblast and inner embryonal mass. This also forms a cavity and is known as a blastocyst and the structure is known as a blastula. This now gets implanted in the uterus. Thus figure b is a blastocyst.

Hence, the correct option is (A).

The oxidation number of cobalt in the complex [Co(NH₃)₆]Cl₃ is +3. It can be calculated as:

Let the oxidation number be x of cobalt:

 x + 6(0) =+3 

∴ No. of Co in complex ion = +3

Hence, the correct option is (B).

Given:

n₁=3 and n₂=4

The magnitude of the electron's angular momentum in 3rd orbit is:

L₁= 3h /2π

The magnitude of the electron's angular momentum in 4th orbit is:

L₂=4h / 2π

Change in angular momentum

Basic nature of oxides increases with increase in the size of cation. 

The increasing order of cations is: Al³⁺ < Mg²⁺ < Na⁺ < K⁺

Therefore the increasing correct order of basic strength is: Al₂O₃ < MgO < Na₂O < K₂O

Hence, the correct option is (B).

Euro III norms, for example, stipulate that sulphur be controlled at 350 parts-permillion (ppm) in diesel and 150 ppm in petrol. Aromatic hydrocarbons are to be contained at 42 percent of the concerned fuel. The goal, according to the roadmap, is to reduce sulphur to 50 ppm in petrol and diesel and bring down the level to 35 percent.

Mass Emission Standards (Bharat Stage II which is equivalent to Euro-II norms) are no more applicable in any of the cities of India.

In the 1990 s, Delhi ranked fourth among the 41 most polluted cities of the world. All the buses of Delhi were converted to run on CNG by the end of 2002.

Hence, the correct option is (C).