This question asks us to identify the correct statements about the Konkan Railway from the given options. Let's analyze each statement individually:

Analyzing Konkan Railway Statements

• Statement (A): It was constructed in 1998.

  The Konkan Railway project was a massive undertaking. The first train ran on the completed Konkan Railway line in 1998, marking the completion of this significant infrastructure project. Thus, statement (A) is correct.

• Statement (B): It connects Roha in Maharashtra to Mangalore in Karnataka.

  The Konkan Railway route officially runs along the western coast of India. It starts from Roha in the Raigad district of Maharashtra and extends southwards to end at Mangalore in Karnataka. This statement accurately describes the geographical extent of the Konkan Railway. Thus, statement (B) is correct.

• Statement (C): It is considered an engineering marvel.

  The Konkan Railway passes through challenging terrains, including the Western Ghats. It features numerous bridges, including high viaducts, and extensive tunnels. The construction involved overcoming significant geographical and engineering hurdles, such as landslides and difficult soil conditions. For these reasons, it is widely regarded as an engineering marvel. Thus, statement (C) is correct.

• Statement (D): The states of Maharshtra, Tamil Nadu and Karnataka are partners in it.

  The Konkan Railway Corporation Limited (KRCL) is a joint venture. Its equity is shared among the Ministry of Railways (Government of India) and the state governments of Maharashtra, Goa, Karnataka, and Kerala. Notably, Tamil Nadu is not one of the partner states involved in the Konkan Railway project. Thus, statement (D) is incorrect.

Determining the Correct Option

Based on our analysis:

• Statement (A) is correct.
• Statement (B) is correct.
• Statement (C) is correct.
• Statement (D) is incorrect.

Therefore, the combination of correct statements is (A), (B), and (C).

Looking at the provided options:

• Option 1: (A), (B) and (D) only - Incorrect because (D) is incorrect.
• Option 2: (A), (B) and (C) only - Correct because (A), (B), and (C) are correct.
• Option 3: (A), (C) and (D) only - Incorrect because (D) is incorrect and (B) is correct.
• Option 4: (B), (C) and (D) only - Incorrect because (D) is incorrect and (A) is correct.

Thus, the correct answer is the one that includes statements (A), (B), and (C) only.