Which of the following is a common type of rider in life insurance?

A term rider is indeed recognized as a common type of rider in life insurance policies. This type of rider provides additional coverage for a specified term to augment the base policy's death benefit. Term riders are often used to meet temporary insurance needs, such as covering the income of a policyholder over a certain period or providing benefits for a specific financial obligation, like a mortgage.

This rider offers more flexible options to policyholders who may have changing insurance requirements over time, allowing them to increase their coverage without needing to purchase a whole new policy. Furthermore, policyholders can usually add a term rider at a relatively low cost compared to the benefits it provides, making it a popular choice for those seeking to enhance their life insurance coverage economically.

Other options, while valid forms of riders, are less commonly used in standard life insurance policies compared to the term rider. The endowment rider generally relates to savings and investment components, which is specific to policies designed with endowment features. Similarly, the investment rider engages more with investment benefits rather than direct coverage enhancements, and a disability rider focuses primarily on income protection due to the insured's inability to work, which can also be considered a different aspect of life insurance coverage.