Please provide me with the correct one.

A poll is to be conducted to determine the proportion p of the students who are in favor of opening a new coffee shop on campus. The students are stratified into undergraduate and graduate students. There are 15000 undergraduate students and 5000 graduate students. A simple random sample of students in each stratum will be selected. The margin of error is 0.05. A preliminarvr estimate of p is not available. If the costs to obtain one observation in undergrad and grad groups are $5 and $3 dollars, respectivelv, what is the required total sample size? a} 39? 435 \"51352 d} 562