【答案】:
A
【解析】:
$-\frac{2}{5}+\left(\frac{5}{8}-\frac{1}{6}+\frac{7}{12}\right)×(-2.4)$
$=-\frac{2}{5}+\left(\frac{5}{8}-\frac{1}{6}+\frac{7}{12}\right)×\left(-\frac{12}{5}\right)$
$=-\frac{2}{5}+\frac{5}{8}×\left(-\frac{12}{5}\right)-\frac{1}{6}×\left(-\frac{12}{5}\right)+\frac{7}{12}×\left(-\frac{12}{5}\right)$
$=-\frac{2}{5}-\frac{3}{2}+\frac{2}{5}-\frac{7}{5}$
$=-\frac{3}{2}-\frac{7}{5}$
$=-\frac{15}{10}-\frac{14}{10}$
$=-\frac{29}{10}$
$=-2.9$
A