If angle $BDC$ is in standard position and its terminal side passes through the point (0, 1), what is the measure of angle $BDC$ in degrees?

• A. $34°$
• B. $56°$
• C. $28°$
• D. $90°$

Answer: (D)

Verified step by step guidance

1. Understand that an angle in standard position has its vertex at the origin (0,0), its initial side along the positive x-axis, and its terminal side passing through a given point.
2. Identify the coordinates of the point through which the terminal side passes, which is (0, 1) in this problem.
3. Recall that the angle's measure can be found by calculating the angle between the positive x-axis and the line connecting the origin to the point (0, 1).
4. Since the point lies on the y-axis above the origin, recognize that this corresponds to a vertical line, which forms a 90-degree angle with the positive x-axis.
5. Conclude that the measure of angle \( \angle BDC \) is 90 degrees because the terminal side is perpendicular to the initial side.