In the following passage some of the words have been deleted. Read the passage carefully and select the correct answer for the given blank out of the four alternatives.

Swollen joints (1)__________ when there is fluid in the tissues around the joints. It can be very (2)_____ and can make it difficult to move the affected joints. In some cases, swelling may cause affected joints to increase in size or appear to be an odd (3)_______ Joint pain and swelling can affect more than one (4)_______ at a time. The most common joints to be (5)_______ by pain and swelling are elbows, wrists, shoulders, the base of the spine, knuckles, hips, knees or ankles.