Given data:
* The resistance of bulb 1 is,

* The resistance of bulb 2 is,

* The voltage across the battery is V = 12 volts.
Solution:
(A). As bulb 2 is unscrewed, thus, the only resistance of the circuit is due to bulb 2.
Thus, the power generated in bulb 1 is,

Substituting the known values,

Thus, the power generated in bulb 1 is 48 watts.
Hence, the fourth option is the correct answer.