Given a short query with keyphrases about a research idea in 2015 in the domain of artificial intelligence, recommend the relevant datasets to validate the research idea from options provided. A short description of the datasets is also provided to help you.

Query: A policy gradient algorithm for learning to act in a stochastic environment.

Keyphrases: stochastic control continuous

Dataset description:
MuJoCo: MuJoCo (multi-joint dynamics with contact) is a physics engine used to implement environments to benchmark Reinforcement Learning methods.
OpenAI Gym: OpenAI Gym is a toolkit for developing and comparing reinforcement learning algorithms. It includes environment such as Algorithmic, Atari, Box2D, Classic Control, MuJoCo, Robotics, and Toy Text.
Mario AI: Mario AI was a benchmark environment for reinforcement learning. The gameplay in Mario AI, as in the original Nintendo’s version, consists in moving the controlled character, namely Mario, through two-dimensional levels, which are viewed sideways.
AI2-THOR: AI2-Thor is an interactive environment for embodied AI. It contains four types of scenes, including kitchen, living room, bedroom and bathroom, and each scene includes 30 rooms, where each room is unique in terms of furniture placement and item types.

Options:- A: MuJoCo  B: OpenAI Gym  C: Mario AI  D: AI2-THOR
MuJoCo