As shown in the figure, the straight line AB is tangent to circle O at point A, the radius of circle O is 1.0, if angle OBA = 30.0, then the length of OB is ()
Choices:
A:1
B:2
C:√{3}
D:2√{3}
Please directly answer the question and provide the correct option letter, e.g., A, B, C, D.
Question: As shown in the figure, the straight line AB is tangent to circle O at point A, the radius of circle O is 1.0, if angle OBA = 30.0, then the length of OB is ()
Choices:
A:1
B:2
C:√{3}
D:2√{3}
Please first conduct reasoning, and then answer the question and provide the correct option letter, e.g., A, B, C, D, at the end.
Question: As shown in the figure, the straight line AB is tangent to circle O at point A, the radius of circle O is 1.0, if angle OBA = 30.0, then the length of OB is ()
Choices:
A:1
B:2
C:√{3}
D:2√{3}