Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.

[Q]: Question: Does interaction of programmed death-1 and programmed death-1 ligand-1 contribute to testicular immune privilege?
Answer: The constitutive expression of PD-L1 in the testis is an important mechanism underlying testicular immune privilege and long-term survival of intratesticular islet allografts.
[A]: yes


[Q]: Question: Do a Profilometric Study to Assess the Role of Toothbrush and Toothpaste in Abrasion Process?
Answer: Besides supporting the fact that toothpaste is needed to create a significant abrasion, this study also showed that a softer toothbrush can cause more abrasion than harder ones. The flexibility of bristles is only secondary to abrasion process and abrasivity of dentifrice has an important role in abrasion process.
[A]: yes


[Q]: Question: Does posterior vaginal wall prolapse correlate with fecal symptoms or objective measures of anorectal function?
Answer: Anorectal symptoms do not correlate with the degree of posterior vaginal wall prolapse, nor does the presence of prolapse equate to abnormal physiologic test results. Bowel symptoms may result from primary anorectal abnormalities, which are demonstrated by physiologic studies.
[A]:
no