Canto 3 -
Araṇya-kāṇḍa
Chapter 64: Rāma Discovers Some Clues About Sītā’s Whereabouts
Text 3.64.33

एवमुक्तस्तु रामेण पर्वतो मैथिलीं प्रति।
शंसन्निव ततः सीतां नादर्शयत राघवे॥

evam uktas tu rāmeṇa parvato maithilīṁ prati
śaṁsann iva tataḥ sītāṁ nādarśayata rāghave

evam = thus; uktaḥ tu = spoke; rāmeṇa = when Rāmacandra; parvataḥ = to the mountain; maithilīm = Maithilī; prati = about; śaṁsan iva tataḥ = it appeared to talk [back to Him]; sītām = [the whereabouts of] Sītā-devī; na adarśayata = [but] it didn’t reveal; rāghave = to Rāghava.

When Rāmacandra thus spoke about Maithilī to the mountain, it appeared to talk [back to Him, but] it didn’t reveal [the whereabouts of] Sītā-devī to Rāghava.

The mountain appeared to talk about Sītā-devī by echoing the question of Lord Rāma. It is implied that Śrī Rāma considered that this was [the mountain’s] disregard [of Him].