Therefore is redundant in this case
Since is giving the reason already

Since the work force is becoming increasingly competitive in light of technological advances and outsourcing, therefore, it is even more basic for students to complete high school and attain at least a bachelor’s degree.

Since the work force is becoming increasingly competitive in light of technological advances and outsourcing, therefore, it is even more basic for students to complete high school and attain at least a bachelor’s degree.

A. therefore, it is even more basic for students to complete high school and attain at least a bachelor’s degree.

B. moreover, it is even more basic for students to complete high school and attain at least a bachelor’s degree.

C. but, it is even more basic for students to complete high school and attain at least a bachelor’s degree.

D. so it is even more basic for students to complete high school and attain at least a bachelor’s degree.

E. it is even more basic for students to complete high school and attain at least a bachelor’s degree.

Since is a subordinate conjunction. The function of a subordinate conjunction is to add a dependent clause to an independent clause (to add more information to the independent clause). By adding such as subordinate conjunction you make a independent clause dependent. Therefore, moreover, but & so are all redundant as the sentence already incorporates "since"

Q: Since the work force is becoming increasingly competitive in light of technological advances and outsourcing, therefore, it is even more basic for students to complete high school and attain at least a bachelor’s degree.

A. therefore, it is even more basic for students to complete high school and attain at least a bachelor’s degree. – the sentence already has ‘since’ to explain the reason so ‘therefore’ is redundant
B. moreover, it is even more basic for students to complete high school and attain at least a bachelor’s degree. - the sentence already has ‘since’ to explain the reason so ‘therefore’ is redundant
C. but, it is even more basic for students to complete high school and attain at least a bachelor’s degree. – sentence reads like a fragment (incomplete)- ‘but’ is unnecessary
D. so it is even more basic for students to complete high school and attain at least a bachelor’s degree. – sentence reads like a fragment (incomplete)- ‘so’ is unnecessary
E. it is even more basic for students to complete high school and attain at least a bachelor’s degree.
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KEY is non-underlined portion.
Sentence starts with [colors=#0000ff]Since[/color] and there are two clauses...indicates cause-effect....or any reasoning...
In A, B, C, D - underlined part starts with conjuctive adverbs - that is redundant. All out

Option E is perfect without any conjunctive adverb.
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