When an advertiser using viewable cost-per-thousand impressions (vCPM) bidding clicks on his own display ad, Quality Score:

  • is not affected because the click is automatically filtered out by Google’s invalid click technology
  • improves for that placement because the vCPM bid decreases
  • improves for that placement because the clickthrough rate (CTR) increases
  • is not affected because clickthrough rate (CTR) is not a factor with vCPM bidding

The correct answer is:

  • is not affected because clickthrough rate (CTR) is not a factor with vCPM bidding

Explanation: CTR is not a factor with vCPM. But there is a metric Active Viewable CTR That Shows how often people clicked your ad after it became viewable.

Read more here: https://support.google.com/adwords/answer/3499086