A data set with $14$ observations contained the following values:
$$2, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 7, ?, ?$$
Where $?$ represents a missing value.

$1$. The standard deviation of the full data set (including the missing values) is:
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A) Lies between $0$ and $1$
.

B) Lies between $1$ and $2$
.

C) Lies between $2$ and $10$
.

D) Lies between $10$ and $20.$

E) Impossible to determine with the given information.