Anxiety causes ulcer. However, some who are happy-go-lucky type also suffer from ulcer. Which of the following would strengthen the association of anxiety and ulcer?

The statement talks about a connection between ulcers and anxiety. However, it also states that some happy-go-lucky people also suffer from ulcers. Now, we need to have a strong set of data to strengthen the connection between ulcers and anxiety. 

1. This option talks about peptic ulcer, which is a specific case of ulcers. Further, this is a mere statement and hence doesn't add value to the original information. Hence, a weak option.

2. Even if anxiety is more harmful than ulcers, we cannot use this to strengthen the association between anxiety and ulcers. 

3. Even if about 90% of women suffer from ulcers, we don't get any input to support the association of ulcers and anxiety. 

4. If more than 65% of the ulcer patients were found to be high on anxiety, we can strongly claim the association of anxiety and ulcers. Hence, a strong statement to substantiate the premise.