Answer:
Answer: Only "She cannot do the work herself" is clearly intensive.
All the others are reflexive. The pronoun serves as a direct object that also refers to (reflects back on) the subject.
Explanation: A possible example for discussion:
The boys bought themselves lunch.
In this sentence, themselves is the indirect object (reflecting the subject) and it serves to mean that the boys bought their own lunch, So reflexive "as-is." If the word is moved to another position in the sentence, it could be intensive.
The boys themselves bought lunch. (Appositive) or The boys bought lunch themselves. In these cases, themselves would be intensive. The meaning changes. Maybe the boys bought lunch for others too. (Surprise! They did it themselves for other people so this makes the most sense and i agree