Alphabet Inc. is plotting to dramatically expand its presence in India, with the possibility of taking millions of square feet in new office space in Bangalore, India’s tech hub.Google’s parent company has leased one office tower and purchased options on two others in Alembic City, a development in the Whitefield tech corridor, totaling 2.4 million square feet, according to people familiar with the deal. The first tower is expected to open to employees in the coming months, while construction on...