22. How many integers $x$ make the triangle with sides $10, 24, x$ have all acute angles?
(A) 4. (B) 5. (C)6. (D) 7. (E) More than 7.
22
22. In any $\triangle ABC$, if $a^{2}<b^{2}+c^{2}$, then the angle opposite to side $a$ is acute. By the Pythagorean theorem, we have
$$
\begin{array}{l}
x^{2}<10^{2}+24^{2}=26^{2}, 24^{2}<10^{2}+x^{2} \\
\Rightarrow 476<x^{2} . \\
\therefore \quad 22 \leqslant x<26 .
\end{array}
$$

The integer values that satisfy the condition are $22,23,24,25$. Therefore, the answer is $(A)$.