。
She trusts the lion.
Literal
[topic-は] lion [object-を] is-trusting.
信頼する ('to trust') takes the trusted entity as a direct object marked with を — distinct from 信じる ('to believe in'), which takes を for the believed proposition. The two verbs differ subtly: 信じる is broader and often religious or evidentiary ('believe a story, believe in God'), while 信頼する specifically denotes interpersonal trust based on character or competence. The ~ている marks the ongoing state of trust.