In the figure, what is the length of the tangent from the external point d to point b?

In the given picture, we are asked to identify and solve for the total length of the tangent line. Such as the solution is shown below:
Tangent line length = length of AB + length of BC + length of CD
Tangent line length = 3 units + 2 units + 2 units
Tangent line length = 7 units

The answer is the letter "C" which is equal to 7.

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