Schistosomiasis, a disease caused by a parasitic worm, is prevalent in hot, humid climates, and it has become more widespread as irrigation projects have enlarged the habitat of the freshwater snails that are the parasite's hosts for part of its life cycle
• Schistosomiasis is a disease that is caused by a parasitic worm.
• It is prevalent in places with hot and humid climate.
• The disease has become more widespread with the increase in irrigation projects.
• These projects have enlarged the habitat of the freshwater snails that play the host of the parasite for a part of its life cycle. Error Analysis:
• Subject “that” that stands for “the freshwater snails” agrees in number and makes sense with the verb “are”. No SV pair error.
• This sentence is providing general facts about the disease and its cause. Hence simple present tense “are“ is correct.
• “that” clause correctly modifies “the freshwater snails” giving information that these snails become host to the parasite for some part in its life.
• There are no pronoun, no parallelism, no idiom and no meaning error errors. Answer Choice Analysis:
A. the freshwater snails that are the parasite's hosts for part of its life cycle: Correct
B. the freshwater snails that are the parasite's hosts in part of their life cycle: Incorrect.
Reference of pronoun “their” distorts the intended meaning of the sentence. Plural “their” now refers to “the freshwater snails” meaning that they are host to the parasite in part of snails’ life cycle and not in part of the parasite’s life cycle. This is not the intended meaning of the sentence.
C. freshwater snails which become the parasite's hosts for part of its life cycles: Incorrect.
Plural “life cycles” is incorrect because a singular “parasite” can have only one life cycle and not multiple life cycles.
D. freshwater snails which become the hosts of the parasite during the parasite's life cycle: Incorrect.
Repetition of “parasite’s” instead of a pronoun makes this choice wordier.
E. parasite's hosts, freshwater snails which become their hostsduring their life cycles: Incorrect.
Same pronoun reference error as in B. Take-Away
1. The pronoun must agree in number with its antecedent.
2. Be vary of the choices that distort he intended meaning of the sentence.
Hope this helps.
haven't we learnt that a pronoun cannot refer to a possessive noun. Unless its here is referring to worm.?
" MGMAT( in a reversal form its earlier rigid stand perhaps) says that the issue of possessive poison is not worth worrying about, since there has been hardly any case that has been rejected on the score of the possessive pronoun’s antecedence in the realm of GMAT.
3. A non possessive pronoun can stand for a non- possessive noun.
Please comment as I have a concept that a pronoun cannot refer to a noun in possessive form.