To find the measure of angle \( GHI \), we use the fact that complementary angles add up to \( 90^\circ \). Given that \( \angle JKL = 34^\circ \) and \( \angle GHI \) is complementary to \( \angle JKL \), we set up the following equation:
\[ \angle JKL + \angle GHI = 90^\circ \]
Substituting the given value for \( \angle JKL \):
\[ 34^\circ + \angle GHI = 90^\circ \]
To solve for \( \angle GHI \), we subtract \( 34^\circ \) from \( 90^\circ \):
\[ \angle GHI = 90^\circ - 34^\circ = 56^\circ \]
Therefore, the measure of \( \angle GHI \) is \( 56^\circ \).
The correct response is:
56°