As TIOBE uses averaged, relative search engine hits for "[programming language name] programming" as its source, it's a significantly lagging indicator, since it counts all pages on the internet equally, regardless of their age. I'm also unsure of the precision of the search "C programming". I suspect that it's catching "C++" in some search engines.
Stack Overflow's annual survey puts JavaScript, SQL, and Python at the top, with C at 12th [0]. RedMonk's Top 20 puts JavaScript, Python, and Java at the top, with C in 10th [1]. ITJobsWatch puts JavaScript, SQL, and C# at top, with C at 9th [2]. Dice puts SQL, Java, and Python as its top 3, with C not even ranking in their top 12 [3]. All of those put JavaScript, Java, and Python in the top 5.
Stack Overflow's annual survey puts JavaScript, SQL, and Python at the top, with C at 12th [0]. RedMonk's Top 20 puts JavaScript, Python, and Java at the top, with C in 10th [1]. ITJobsWatch puts JavaScript, SQL, and C# at top, with C at 9th [2]. Dice puts SQL, Java, and Python as its top 3, with C not even ranking in their top 12 [3]. All of those put JavaScript, Java, and Python in the top 5.
[0] https://insights.stackoverflow.com/survey/2021#most-popular-...
[1] https://redmonk.com/kfitzpatrick/2021/03/02/redmonk-top-20-l...
[2] https://www.itjobswatch.co.uk/default.aspx?ql=&ll=&id=900&p=...
[3] https://insights.dice.com/2021/01/05/top-12-programming-lang...