Which term describes conditions or situations that prevent success or development?

The term that describes conditions or situations that prevent success or development is "adverse." This word is often used in contexts where obstacles or unfavorable circumstances hinder progress or achievement. Adverse conditions can include anything from economic downturns and challenging environments to lack of resources or support, all of which can impede one's ability to succeed.

In contrast, the other terms refer to positive situations: "favorable" denotes conditions that are conducive to success, while "supportive" describes scenarios where help or assistance is present, thereby promoting development. Similarly, "beneficial" implies an advantage or a situation that positively impacts outcomes. Therefore, while the other options signify helpful or positive attributes, "adverse" specifically identifies the hindrances to progress, making it the correct choice.