Colin Has Computed the Variance for His 10 Raw Scores $S_{X}^{2}$

Multiple Choice

Colin has computed the variance for his 10 raw scores and obtained = 16.37.He then computed $S_{X}^{2}$ $S \bar{X}$ as follows: $s \bar{x}=\sqrt{\frac{4.046}{10}}=0.636$ What is wrong?

A) Colin first took the square root of $S_{X}^{2}$ and put this into the formula for $S \bar{X}$ .He should have used the $S_{X}^{2}$ = 16.37 value.
B) Colin should have divided here by N - 1.
C) Colin should not have taken the square root of 4.046/10 because he needs $S_{X}^{2}$ in the formula for the t-test.
D) There is nothing wrong with the way Colin has done this problem.