Here are the odd one out choices for each question:

**Câu 1:**
**B. celebrate** - The other words (A, C, D) are adjectives/nouns while "celebrate" is a verb.

**Câu 2:**
**A. pesticide** - The other words (B, C, D) are nouns related to processes or roles, whereas "pesticide" refers specifically to a chemical substance.

**Câu 3:**
**B. badminton** - The other words (A, C, D) are abstract nouns, while "badminton" is a specific sport.

**Câu 4:**
**D. construction** - The other words (A, B, C) are adjectives, while "construction" is a noun.

**Câu 5:**
**C. dominant** - The other words (A, B, D) can imply actionable behavior (business actions, embarrassment, decoration), while "dominant" is a descriptive adjective.

**Câu 6:**
**D. invader** - The other words (A, B, C) deal with legality and regulations, while "invader" is a noun describing a person.

**Câu 7:**
**B. beautiful** - The other words (A, C, D) can be related to conditions or events, whereas "beautiful" is an adjective describing aesthetic quality.

**Câu 8:**
**C. efficient** - The other words (A, B, D) relate to concepts or instances, whereas "efficient" is an adjective.

**Câu 9:**
**B. envelope** - The other words (A, C, D) describe characteristics of people or actions, while "envelope" is an object.

**Câu 10:**
**C. occupy** - The other words (A, B, D) relate to occurrences or events, while “occupy” is an action.

**Câu 11:**
**B. competent** - The other words (A, C, D) are related to business or commerce, while "competent" pertains to capability.

**Câu 12:**
**B. kangaroo** - The other words (A, C, D) describe qualities of people or behaviors, while "kangaroo" is a specific animal species.

**Câu 13:**
**D. policeman** - The other words (A, B, C) refer to abstract concepts or phenomena, while "policeman" is a specific role.

**Câu 14:**
**B. horizon** - The other words (A, C, D) involve actions or processes, whereas "horizon" is a physical feature.

**Câu 15:**
**B. acacia** - The other words (A, C, D) refer to attributes or qualities, while "acacia" is a type of tree.