Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

Problem: the total marks obtained by a student in mathematics and physics is 50 and his score in chemistry is 20 marks more than that in physics. find the average marks scored in mathamatics and chemistry together.
Options: a. 15, b. 25, c. 35, d. 45, e. 55
c

Problem: find the area of a parallelogram with base 10 cm and height 20 cm.
Options: a. 200, b. 384, c. 200, d. 244, e. 242
c

Problem: one - third of rahul ' s savings in national savings certificate is equal to one - half of his savings in public provident fund. if he has rs. 1, 90,000 as total savings, how much has he saved in public provident fund ?
Options: a. 80000, b. 60000, c. 50000, d. 76000, e. 90000
d