Read the given statements and select the correct option.
(i)Synaptic cleft of neurons secreates adrenaline.
(ii)Myelinated nerve fibres are enveloped with Schwann cells, which form a myelin sheath around the axon.
(iii)Non-myelinated nerve fibre is enclosed by a Schwann cell that does not form a myelin sheath.
(iv)Spinal and cranial nerves are made of non-myelinated nerve fibres.

Options

A. Statements (i) and (ii) are correct but statements (iii) and (iv) are incorrect.
B. Statements (i), (ii) and (iii) are correct but statement (iv) is incorrect.
C. Statements (iii) and (iv) are correct but statements (i) and (ii) are incorrect.
D. Statement (ii) and (iii) are correct but statements (i) and (iv) are incorrect.

Answer

D

Explanation

Synaptic vesicles of the synaptic knob secrete neurotransmitter (e.g. , adrenaline).Spinal nerves and cranial nerves are myelinated nerves.