You are given a science question (easy-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

[EX Q]: Two workers are using a scaffold. One worker weighs 180 lbs. and the other weighs 200 lbs. Impact effects are assumed to increase the live load of the workers' weight by 25 percent. What is the resultant maximum live load, in pounds, that can be expected from the two workers supported by the scaffold?  
 (A) 380 lbs. (B) 475 lbs. (C) 625 lbs. (D) 950 lbs.
[EX A]: B

[EX Q]: A student walking quickly while carrying an orange on his lunch tray stops suddenly. The orange will most likely roll off the tray due to  
 (A) inertia of the orange. (B) centripetal force of the orange. (C) the friction acting on the orange. (D) the balanced forces acting on the orange.
[EX A]: A

[EX Q]: Most scientists agree that an increase in the amount of greenhouse gases entering Earth's atmosphere causes  
 (A) a decrease in sea level (B) a decrease in average surface temperatures (C) an increase in melting of polar ice caps (D) an increase in crustal plate movement
[EX A]:
C