Let the number of boys in the class be represented by \( b \). Since there are 156 more girls than boys, the number of girls can be represented as \( b + 156 \).
According to the problem, the total number of students in the class is 498. Therefore, we can set up the following equation:
\[ b + (b + 156) = 498 \]
This simplifies to:
\[ 2b + 156 = 498 \]
Next, we will subtract 156 from both sides of the equation:
\[ 2b = 498 - 156 \] \[ 2b = 342 \]
Now, divide both sides by 2 to solve for \( b \):
\[ b = \frac{342}{2} = 171 \]
So, the number of boys in the class is \( \textbf{171} \).
The correct answer is:
A. 171 boys