Answer:
According to the Washington post article, prices of healthcare cost, utilities and housing has increased faster than social security benefits.
According to it, social security grew 43% between 2005 and 2015. But, monthly housing cost rose by 44% while renting cost increased 56%. Further, price of heating oil increased 159% and price of electricity by 63%. Lastly, cost of landline phone service increased by 52%.
So the answer is electricity, heating oil, and rent.