For the following questions, statement as well as the reason(s) are given. Each questions has four options. Select the correct option.
(a) Statement $-1$ is true, statement $-2$ is true; statement $-2$ is the correct explanation of statement $-1$.
(b) Statement $-1$ is true, statement $-2$ is true but statement $-2$ is not the correct explanation of statement $-1$.
(c) Statement $-1$ is true, statement $-2$ is false
(d) Statement $-1$ is false, statement $-2$ is true
(A) a
(B) $b$
(C) $\mathrm{c}$
(D) $\mathrm{d}$
Statement $-1$ : If a spring having spring constant $\mathrm{k}$ is divided into equal parts, then the spring constant of each part will be $2 \mathrm{k}$. Statement $-2:$ When the length of the elastic spring is increased ( stretched) by $\mathrm{x}$, then the amount of work required to be done is $(1 / 2) \mathrm{kx}^{2}$
(A) a
(B) $\mathrm{b}$
(C) $\mathrm{c}$
(D) d