Even today many people are guided by abstruse moral values.

irrational
obscure
impracticable
dangerous

The correct answer is: B. obscure

Abstruse means difficult to understand or comprehend. Moral values are principles that guide a person’s behavior in relation to what is right and wrong. So, abstruse moral values are moral values that are difficult to understand or comprehend.

Here are brief explanations of the other options:

  • A. irrational means not based on or in accordance with reason. Moral values are often based on reason, so it is unlikely that they would be considered irrational.
  • C. impracticable means not able to be put into practice. Moral values are often guides for behavior, so it is likely that they can be put into practice.
  • D. dangerous means likely to cause harm or injury. Moral values are often intended to promote good and prevent harm, so it is unlikely that they would be considered dangerous.