1.DNA, ___, is found in the cell nucleus in the form of very long and thin molecules consisting of two spiral strands.
A.inherits materialB.is inheritance material
C.material is inherited
D.the material of inheritance
2.Potential dehydration is ___ that a land animal faces.
A.the often greatest hazardB.the greatest often hazard
C.often the greatest hazard
D.often the hazard greatest
3.Before every presidential election in the United States, the statisticians try to guess the proportion of the population that ___ for each candidate.
A.are votedB.voting
C.to be voted
D.will vote
4.Although thunder and lightning are produced at the same time, light waves travel faster ___, so we see the lightning before we hear the thunder.
A.than sound waves doB.than sound waves are
C.do sound waves
D.sound waves
5.All the committee members said the lecture was ___ a second time.
A.worth to listenB.worth being listened to
C.worth listening to
D.worth to listen to