Which one of following is employed as a tranquilizer?

Tranquilizers are drugs used to treat stress, anxiety and mental diseases; they relieve tension by inducing a sense of well-being.
Equanil (meprobamate) is a mild tranquilizer used in controlling depression and hypertension.
Chlorpheniramine is an antihistamine (anti-allergic drug).
Naproxen is a non-narcotic analgesic and anti-inflammatory drug.
Tetracycline is a broad-spectrum antibiotic.
Hence the tranquilizer is equanil.