 )
          .attr("stroke", function(d){ return myColor(selectedGroup) })
    }

    // When the button is changed, run the updateChart function
    d3.select("#selectButton").on("change", function(event,d) {
        // recover the option that has been chosen
        const selectedOption = d3.select(this).property("value")
        // run the updateChart function with this selected option
        update(selectedOption)
    })

})
</script></xmp></code></pre>
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