Answer: B. Espero que
Espero que te guste el libro que te voy a prestar.
I hope you like the book I'm going to lend you.
Explanation: the subjunctive mode is used in expressions of will, doubt or suggestion. Since the verb in this sentence is in subjunctive mode, "te guste", we have to use an expression of wish. "Espero que te guste" that means I hope you like it.