A

To find the work done in blowing a soap bubble, we need to understand that a soap bubble has two surfaces due to its thin film structure. The total surface area of the bubble is given by the formula for the surface area of a sphere:
Surface Area (S) = 4πr².
Since there are two surfaces in a soap bubble, the effective surface area becomes:
Total Surface Area (A) = 2 × 4πr² = 8πr².
The work done (W) in blowing the soap bubble against the surface tension (T) is given by:
W = Surface Tension × Total Surface Area
Therefore, W = T × 8πr².
Thus, the work done in blowing a soap bubble of radius r is 8πr²T.
Hence, the correct answer is (A) 8πr²T.