Reading left to right, which list shows investments increasing in risk level?

Stock, CD, mutual fund

Mutual fund, CD, stock

Mutual fund, stock, CD

CD, mutual fund, stock

CD, mutual fund, stock

Explanation:

CDs' are government loans. Any government investment or loan is risk-free. Therefore, it is less risky.

The mutual fund has a few risks because it has the aim of increasing revenue. Anything which has a probability of getting profit, there must be a specific risk. However, a mutual fund's risk is low but higher than the CD.

The stock price is increasing at times and decreasing another time. Therefore, it is riskier than mutual funds and CD.

So the sequence is CD, mutual fund, stock.