On simplification, the expression $$1 \div \left\{\frac{1}{2} + \frac{5}{2} of \frac{1}{5} - \left(\frac{1}{4} \div \frac{1}{2} + \frac{1}{2} \times\3right)\right\}$$

A

0

B

-1/2

C

1/2

D

2/3