The judge ruled that the evidence was inadmissible on the grounds that it was ________ to the issue at hand.
句意：法官裁定证据无效，理由是它与目前的案件无关。irrelevant意为“无关的”。irrational 指“无道理的（言行等）”。unreasonable意为“超越情理的，过分的”。invalid指“无根据的，站不住脚的（论 据，要求等）；不予正式承认的，无效的”。故选D。