(2) In a positive arithmetic sequence $\left\{a_{n}\right\}$ with a common difference of 4, the arithmetic mean of $a_{3}$ and 2 is equal to the geometric mean of $S_{3}$ and 2, where $S_{3}$ represents the sum of the first 3 terms of the sequence. Then the value of $a_{10}$ is ( ).
(A) 38
(B) 40
(C) 42
(D) 44
(2) Since the common difference $d=4$ of the arithmetic sequence $\left\{a_{n}\right\}$, then $a_{3}=a_{1}+8, S_{3}=3 a_{1}+12$, thus
$$
\frac{\left(a_{1}+8\right)+2}{2}=\sqrt{2\left(3 a_{1}+12\right)},
$$

solving for $a_{1}=2$. Therefore,
$$
a_{10}=2+9 \times 4=38 \text {. }
$$

Hence, the answer is A.