Convert 45 degrees to radians.

To convert degrees to radians, you can use the conversion factor that π radians is equivalent to 180 degrees. The formula to convert degrees (θ) to radians (r) is:

r = θ × (π / 180).

In this case, you are converting 45 degrees to radians. By applying the formula:

r = 45 × (π / 180).

This simplifies to:

r = 45π / 180.

To reduce this fraction, divide both the numerator and the denominator by 45:

r = π / 4.

Thus, 45 degrees is equal to π/4 radians. This confirms that the correct answer is the choice representing π/4 radians, which accurately reflects the conversion from degrees to radians based on the conversion ratio.

The other options represent different angles and therefore do not yield the correct conversion for 45 degrees.