Explanation
A salvaged wood door from another site qualifies under the Materials and Resources sustainable criteria of materials reuse. Materials reuse is the practice of using existing materials or products for new purposes without altering their form or composition. Materials reuse reduces the demand for virgin materials, saves energy and resources, and prevents waste generation. The other options are not applicable to a salvaged wood door from another site. Certified wood is wood that has been harvested from forests that are managed in an environmentally responsible, socially beneficial, and economically viable manner according to the standards of an accredited certification system such as the Forest Stewardship Council (FSC). Bio-based materials are materials that are derived from plants or animals, such as bamboo, cork, wool, or cotton. Waste diversion is the practice of diverting waste from landfills or incinerators by recycling, reusing, salvaging, or donating materials. References: LEED Green Associate Candidate Handbook, page 28; USGBC, [Materials and Resources], page 4.

Explanation
LEED for Neighborhood Development (LEED ND) is a rating system that aims to inspire and help create better, more sustainable, well-connected neighborhoods1. It looks beyond the scale of buildings to consider entire communities1. One of the main goals of LEED ND is to reduce vehicle miles traveled (VMT) and greenhouse gas emissions by promoting the location and design of neighborhoods that are accessible by foot or public transportation234. Therefore, LEED ND encourages development within and near existing communities or public transportation infrastructure, which is option C.
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LEED certification for neighborhood development
LEED for Neighborhood Development - Wikipedia
LEED for Neighborhood Development - Grow Smart RI
LEED for Neighborhood Development - s3.amazonaws.com

Explanation
Recycling is a strategy that can be used to reduce the amount of construction waste that is sent to landfills or incinerators. Recycling involves collecting, sorting, processing, and reusing or selling materials that would otherwise be discarded as waste. Recycling can save natural resources, reduce greenhouse gas emissions, create jobs, and lower disposal costs1 . References: LEED v4 Green Associate Candidate Handbook1, EPA's Recycling Basics

The triple bottom line is a business concept that states firms should commit to measuring their social and environmental impact-in addition to their financial performance-rather than solely focusing on generating profit, or the standard "bottom line"1. The triple bottom line can be broken down into "three P's": profit, people, and the planet2. Firms can use these categories to conceptualize their environmental responsibility and determine any negative social impacts to which they might be contributing1.