Ways developed countries can support sustainable transition

The text states that developing countries are specifically "hampered by the high costs and low availability of clean energy sources." It then concludes that "Developed countries need to support developing countries' transition."

The logical mechanism of support is directly resolving the stated hurdle: making clean energy available at a low cost (Statement 1).

While developed countries invest in public transport for themselves, providing "nominal interest rate loans" (Statement 2) is a highly specific financial mechanism never mentioned in the text. Similarly, "encouraging them to change" (Statement 3) is a generic platitude that ignores the explicit financial/resource hurdle identified by the author.

Answer: (a).