Which of the following statements is true of spreadable margarines made from polyunsaturated oils?
a. they are less resistant to damage from oxidation.
b. they have more points of unsaturation than the original oil.
c. they have a high smoking point, so they are suitable for frying foods at high temperatures.
d. they are made by forcing oxygen through the oil.
e. they are made by dehydrogenating saturated fats.