In this task, we ask you to rewrite a sentence in simple English without changing its general meaning. Essentially, you want to make the sentence easier to read by using simpler words, utilizing more straightforward sentence structures, and omitting non-essential information etc.

Constitutional economics is a research program in economics and constitutionalism that has been described as explaining the choice " of alternative sets of legal-institutional-constitutional rules that constrain the choices and activities of economic and political agents " .
Constitutional economics tries to explain the selection of constitutional rules " limiting the choices and activities of economic and political agencies . "

The incarnation is commemorated and celebrated each year at Christmas , and also reference can be made to the Feast of the Annunciation ; " different aspects of the mystery of the incarnation " are celebrated at Christmas and the Annunciation .
The Incarnation is commemorated and celebrated each year at the Feast of the Incarnation , which is better known as the Annunciation .

An online pharmacy , internet pharmacy , or mail-order pharmacy is a pharmacy that operates over the internet and sends the orders to customers through mail or shipping companies .

An online pharmacy is a pharmacy that operates on the Internet to sell medications to consumers .