JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">

</div>

JavaScript

// assume the data is json.feed.category
var data = [{
  term: "Adbc"
}, {
  term: "acc"
}, {
  term: "Abcc"
}, {
  term: "bc"
}, {
  term: "Bbc"
}, {
  term: "dbc"
}, {
  term: "1bc"
}];

var cat = function(categories) {
  var listspan = document.createElement('span');
  listspan.id = 'listspan';

  categories
    // get the labels starting with "A" ONLY.
    .filter(function(category) {
      return category.term.toLowerCase().indexOf('a') === 0;
    })
    // not required
    .sort(function(a, b) {
      return +(a.term > b.term) || +(a.term === b.term) - 1;
    })
    // insert a tag to listspan, instead of using string, this way maybe more efficient.
    .forEach(function(category) {
      var a = document.createElement('a');
      a.href = 'search/label/' + category.term;
      a.innerText = category.term;
      listspan.appendChild(a);
      listspan.appendChild(document.createElement('br'));
    });

  // insert the list to DOM
  document.getElementById('container').appendChild(listspan);
}

cat(data);