OFFICIAL EXPLANATION
Artists who are experienced and successful usually suggest that beginners practiced with determination and patience.A. Artists who are experienced and successful usually suggest that beginners practiced
This answer choice is grammatically incorrect. Suggest is one of the nine verbs to which the Subjunctive rule applies (if it is followed by that). This means that the next verb after suggest that should be in base form. However, practiced is not in base form.
What helps us identify this question as a Subjunctive question as well as identify the mistake is the following Stop Sign:
propose/recommend/require/request/insist/suggest/mandate/ask/demand that
Whenever you come across this Stop Sign, make sure that the following verb is in its base form.B. Experienced and successful artists usually suggest that beginners practice
This answer choice corrects the original Subjunctive error by using a base form verb (practice) after suggest that.C. Artists which are experienced and successful usually suggest that beginners practice
While this answer choice corrects the original Subjunctive error by using the base form verb practice after suggest that, it is grammatically incorrect. The relative pronoun which cannot begin a relative clause that modifies a human noun (Artists).
What helps us identify this question as a Relative Clause question as well as identify the mistake is the following Stop Sign:
who, which, that, whose, whom
D. Artists who are successful and experienced usually suggest that beginners will practice
This answer choice is grammatically incorrect and repeats the original Subjunctive error. Suggest is one of the nine verbs to which the Subjunctive rule applies (if it is followed by that). This means that the next verb after suggest that should be in base form. However, will practice is not in base form.
What helps us identify this question as a Subjunctive question as well as identify the mistake is the following Stop Sign:
propose/recommend/require/request/insist/suggest/mandate/ask/demand that
Whenever you come across this Stop Sign, make sure that the following verb is in its base form.E. Artists who are both experienced and also successful usually suggest that beginners practice
While this answer choice corrects the original Subjunctive error by using the base form verb practice after suggest that, the clause who are both experienced and also successful usually is overly wordy and therefore redundant. There is a more concise answer choice.