Question

People who are lonely: 1. make an effort in talking with others and are therefore good conversational partners. 2. often have drab or dull interactions with others as they tend to have negative attitudes toward others. 3. try too hard to establish intimacy and self-disclose too much. 4. think that all others are open to interactions and therefore keep trying even when others don't want to converse with them

Answer 1

I believe the answer is 2. often have drab or dull interactions with others as they tend to have negative attitudes toward others.

To put in in a more simple statement, lonely people cannot Grasp the correct way to establish relationship with other people.
This could happen because of several reason, such as extreme shyness, emotional trauma from the past, difference in intellectual level, etc.