Instruments which indicate pitch in one manner or another are the attitude indicator, the airspeed indicator, the sensitive pressure altimeter and the vertical speed indicator.

That would be the attitude indicator as this is gyro driven the rest are dependent on measuring pressure changes and tend to lag a bit.

Attitude indicator is the only flight instrument that gives you an instantaneous indication of attitude changes.

The artificial horizon.

the vsi is unreliable when flying..i am a glider pilot.and l prefer to use a variometer.a more sensitive vertical speed indicator..very little lag.and will immediatly indicated lift and sink

Check the question. l believe it is actually asking which instrument will reflect a change in altitude first. If that is the case, the answer is the VSI. The VS l immediately indicates a change in vertical speed trend, but lags by 7 to 9 seconds when settling onto the rate of change in vertical speed. It is for this reason that it is the single most useful instrument when doing unusual attitude recoveries under the hood.

Edit: Really? l got a thumbs down for saying something that is true? Sheesh. OK down with diplomacy.

Everyone above me is WRONG & here is why. The immediate trend information displayed on the VS l is sensitive to much smaller variations than any other instrument. A 1 degree pitch change on the A l will hardly be noticed, but will be immediately reflected on the VS l as the needle swings rapidly upward or downward. It may take a few seconds for the RATE information to be accurate, but the initial trend is immediate. A change as slight as 5-10 feet of altitude will be reflected on the VS l whereas on the altimeter it wo not even be noticed. Go ahead & believe those above me if u like, but l am right & they r wrong. Period.

Check the question.

It asks about attitude.

There is no mention of altitude.