If two angles are complementary to each other, then each angle is :

Options

A. a right angle
B. a supplementary angle
C. an obtuse angle
D. an acute angle

Answer

To solve the question, we need to understand the definition of complementary angles.

### Step 1: Define Complementary Angles
Complementary angles are two angles whose measures add up to 90 degrees.

### Step 2: Analyze the Options
We need to evaluate the options given in the question:
- **Right Angle**: An angle that measures exactly 90 degrees.
- **Supplementary Angle**: Two angles that add up to 180 degrees.
- **Obtuse Angle**: An angle that measures more than 90 degrees but less than 180 degrees.
- **Acute Angle**: An angle that measures less than 90 degrees.

### Step 3: Determine the Characteristics of Complementary Angles
Since complementary angles add up to 90 degrees, it implies that:
- If one angle is a right angle (90 degrees), the other angle must be 0 degrees, which is not valid in this context.
- Both angles cannot be obtuse, as that would exceed 90 degrees.
- Both angles can be acute, as they can be less than 90 degrees and still add up to 90 degrees.

### Step 4: Conclusion
Therefore, each angle in a pair of complementary angles can be acute, but they cannot both be right angles. The correct answer is that each angle is an acute angle.

### Final Answer
Each angle is an acute angle.

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