Find $d y / d u , d u / d x \text {, and } d y / d x$

Multiple Choice

Find $d y / d u , d u / d x \text {, and } d y / d x$ of the functions $y = u ^ { 2 } , u = 4 x + 7$ .

A) $d y / d u = 2 u , d u / d x = 4 , \text { and } d y / d x = 32 x + 56$
B) $d y / d u = 2 u , d u / d x = 2 \text {, and } d y / d x = 16 x + 49$
C) $d y / d u = 4 u , d u / d x = 4 , \text { and } d y / d x = 32 x + 56$
D) $d y / d u = 4 u , d u / d x = 2 , \text { and } d y / d x = 32 x + 56$
E) $d y / d u = 2 u , d u / d x = 4 \text {, and } d y / d x = 16 x + 49$