When the Necessary Conditions Are Met in Testing $H _ { 0 } : p _ { 1 } - p _ { 2 } = 0 \text { versus } H _ {0} : p _ { 1 } - p _ { 2 } \neq 0$

When the necessary conditions are met in testing $H _ { 0 } : p _ { 1 } - p _ { 2 } = 0 \text { versus } H _ {0} : p _ { 1 } - p _ { 2 } \neq 0$ the two sample proportions are $\hat { p } _ { 1 } = .40 \text { and } \hat { p } _ { 2 } = .30 \text {, and } V \left( \hat { p } _ { 1 } - \hat { p } _ { 2 } \right) = .0016 \text { when } H _ { o }$ is true. Then, the value of the test statistic is

A) 10.0
B) 2.5
C) 7.5
D) 62.5
E) 0.70