Option 1 states that the main purpose of setting up railways in India was to serve the interest of the empire. This means that the railways were built primarily to benefit the British colonial rulers and their economic interests.

Option 2 states that British capital investments were invited with a guaranteed interest of 15%, which could be paid from Indian revenues if necessary. This means that the British government offered financial incentives to attract British investors to invest in railway construction projects in India.

Option 3 states that the construction of railways in colonial India disturbed the ecology. This suggests that the building of railways had negative environmental impacts, such as deforestation and disruption of natural habitats.

Option 4 states that the construction of railways in colonial India was planned in such a way that it connected internal markets with ports, but did not provide interconnection between internal market cities. This means that the railways were designed mainly to facilitate the transport of goods between internal markets and ports, rather than improving connectivity and transportation within the country.

Based on these options, it can be concluded that option 2 - the invitation of British capital investments with guaranteed interest - was NOT a feature of railways in colonial India. This means that the statement in option 2 is not true, and the correct answer is option 2