Health experts advise people to limit their consumption of sweet foods because of high levels of fat sugar and cholesterol.

Correct sentence -Health experts advise people to limit their consumption of sweet foods because of high levels of fat, sugar, and cholesterol.

In this sentence, the items in a series are part of the dependent clause. The word "because" signals that the rest of the sentence after it relies upon the preceding part of the sentence. Used correctly, the commas here separate fat, sugar, and cholesterol into three distinct items.

The manager asked the employees to bring three items on the field trip, sunscreen, money, and an umbrella.

Correct sentence - The manager asked the employees to bring three items on the field trip: sunscreen, money, and an umbrella.

In this sentence, a colon is used to signal that a list of items follows.

The term "climbers" can refer to a number of different plants such as the sweet gourd, bitter gourd, and Grapevine Passionflower.

Correct answer: The term "climbers" can refer to a number of different plants, such as the sweet gourd, bitter gourd, and Grapevine Passionflower.

As it is written, the only acceptable choice uses a comma. A semicolon or period results in a fragmented second half of the sentence.