1.In a cross-sectional study of the association between herpes 2 infection and increased risk for HIV infection, the authors say, "Our data are limited because we did not establish whether genital herpes infection preceded HIV infection, although evidence suggests that genital herpes is often acquired at a younger age than HIV."

2.In this statement, they are trying to demonstrate support for this criterion even though they cannot do so fully:

3.a.Strength of the association

4.b.Temporality

5.c.Dose-response

6.d.Experiment

7.e.Plausibility/Coherence

8.f.Consistency

9.