Which of the following is correct?

a.sin1∘
b.sin1∘>sin1

c.sin1∘=sin1

d.sin2∘=sin2

To solve this question, let's analyze the options and the context carefully.

### Key points:
1. **Degrees and Radians**:
- In trigonometry, angles can be measured in degrees (°) or radians.
- \(1^\circ\) means "1 degree," while \(1\) without the degree symbol refers to \(1\) radian.
- Recall that \( \pi \) radians = \( 180^\circ \). Therefore, \(1^\circ\) in radians is \( \frac{\pi}{180} \) radians, which is much smaller than 1 radian (approximately 0.01745 radians).

2. **Behavior of the sine function**:
- For small angles close to \(0\), the sine function is nearly linear. For small positive values of \(x\), \(\sin(x)\) increases as \(x\) increases.

3. **Comparison of \(\sin(1^\circ)\) and \(\sin(1)\)**:
- Since \(1^\circ\) (in radians) is much smaller than \(1\) radian, \(\sin(1^\circ)\) corresponds to a much smaller angle and will therefore have a smaller value than \(\sin(1)\).

### Verifying the options:
- \( \sin(1^\circ) < \sin(1) \): This is true because \(1^\circ\) (in radians) is much smaller than \(1\), and the sine of a smaller angle is smaller.
- \( \sin(1^\circ) > \sin(1) \): This is false, as explained above.
- \( \sin(1^\circ) = \sin(1) \): This is false because the angles \(1^\circ\) and \(1\) radian are not the same.
- \( \sin(2^\circ) = \sin(2) \): This is also false because \(2^\circ\) and \(2\) radians are not equal.

### Correct answer:
a. \(\sin(1^\circ) < \sin(1)\)