1. Catalyst
a) aid to a process
b) bright colour
c) guarantee
d) ancestor
2. Laborious
a) tedious
b) radical
c) hard-working
d) knowledgeable
3. Irrefutable
a) strange
b) blocked
c) certain
d) inferior
4. Advocate
a) copy
b) misunderstand
c) support a cause
d) leave quickly
5. Elaborate
a) infected
b) internal
c) detailed
d) struggling
6. Degrade
a) humiliate
b) inspect
c) flatten
d) lower
7. Economical
a) rich
b) avoiding waste
c) common
d) religious
8. Differentiate
a) disagree
b) create
c) vary randomly
d) identify differences between
9. Anomaly
a) agreement
b) retirement
c) oddity
d) forgetfulness
10. Constraint
a) limit
b) tightness
c) defense
d) anxiety
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