During the peak hours they were ____by the heave traffic.A. held forwardB. held backwardC. held downD. held up

此题考查的是短语辨析。在高峰时段，由于交通拥堵，他们被耽搁了。选项中，held forward意为“被提前”，held backward意为“被向后推”，held down意为“被压制”，held up意为“被耽搁，被延误”。根据题意，正确答案是D选项，held up。