Please please answer correct with reason in detail, other wise skip it

Please do not provide useless explanation, I need correct answer please

Question 12 1 pts Which of the following is true about the probability density function (pdf) of a continuous random variable? The area underneath it must be positive and strictly less than one ( cdf(y)-cdf(x) represents the probability the random variable is less than y but greater than or equal to x. You may assume yxx and cdf stands for the cumulative density function, O You have to be careful to note the '=' part of any inequalities when working out probabilities It can never be higher than one, because probabilities are never higher than one