SVG text inside x and y axis

 svg.append("text")

    .style("fill", "black")

    .attr("x", 200)

    .attr("y", 100)

    .text("Hello World");

refereces:- d3nood.org/2014/02/d3js-elements.html

leanpub.com/d3-t-and-t-v4/read