Among the options given, the statement "They tend to be larger than younger stars" is generally true for older stars, particularly those in advanced stages of their lifecycle, such as red giants. However, it is important to note that there are various factors that can affect a star's size, brightness, and overall characteristics, including its initial mass and stage of evolution.
On the other hand, older stars can also appear duller in comparison to younger, hotter stars that are often more luminous and brighter. Ultimately, it's crucial to consider the context of the star's evolutionary phase when discussing age-related characteristics.