To simplify \( 37x + 27x \), you can combine the like terms (the coefficients of \( x \)):
\[ 37x + 27x = (37 + 27)x = 64x \]
However, this answer does not appear in the responses you've provided. It seems there may be a misunderstanding or error.
The correct simplification yields \( 64x \), but from your choices, none match this. Please check the options again.