# If $\overrightarrow{A} = \hat{i} + \lambda \hat{j} + \hat{k}, \; \overrightarrow{B} = \hat{i} + \hat{j} + \hat{k}$, then for $|\overrightarrow{A} + \overrightarrow{B}| = |\overrightarrow{A} | + |\overrightarrow{B}|$ to be true, the value of $\lambda$ is equal to :
( A ) $2$
( B ) $-2$
( C ) $-1$
( D ) $1$