Read the given passage and answer the questions that follow.
Climate policy must now put health at the centre and promote climate change mitigation policies that bring health benefits simultaneously. Health-focused climate policy would help bring about a planet that has cleaner air, more abundant and safer freshwater and food, more effective and fairer health and social protection systems and, as a result, healthier people. Investment in clean energy will yield health gains that repay those investments twice over. There are proven interventions able to reduce emissions of short-lived climate pollutants, for instance applying higher standards for vehicle emissions, which have been calculated to save approximately 2.4 million lives per year, through improved air quality and reduce global warming by about 0.5°C by 2050. The cost of renewable sources of energy has decreased significantly in the last few years, and solar energy is now cheaper than coal or gas in most major economies.
Which is the best description of the tone of the passage?