A:who B:whom C:which D:that

A:from B:in C:by D:against

The river {{U}}widens{{/U}} considerably as it begins to turn east.

A:extends B:stretches C:broadens D:traverses

The development of the transistor and integrated circuits revolutionized the electronics industry by allowing components to be packaged more {{U}}densely{{/U}}.

A:compactly B:inexpensively C:quickly D:carefully

The use of the chemical may present a certain {{U}}hazard{{/U}} to the laboratory workers.

A:protection B:indication C:immunity D:danger

Many economists have given in to the fatal {{U}}lure{{/U}} of mathematics.

A:error B:function C:attraction D:miracle

We have got to {{U}}abide by{{/U}} the roles.

A:stick to B:persist in C:safeguard D:apply

The children {{U}}trembled{{/U}} with fear when they saw the policeman.

A:wept B:cried C:ran D:shook

Although originally a German innovation, kindergarten got its real start in the United States as a movement to provide {{U}}an improved{{/U}} learning environment for children.

A:an easy B:a playful C:an open D:a better

In their productions, choreographers of modem dance have introduced humor, protested social injustice, and {{U}}probed{{/U}} psychological problems.

A:solved B:explored C:involved D:disputed